Electric demand instrument.



' W. J. LLOYD. -ELBGTRIG DEMAND INSTRUMENT. APPLIOATION FILED JAN-.16, 1905.

* 919 605 Patented Apr. 27, 1909.

Witnesses: Inventor:

j William J. Llogd, 442 b MMM netio material WILLIAM J. LLOYD, OF PITTSFIELD,

MASSACHUSETTS, ASSIGNOR, BY MESNE ASSIGLQMENTS,

TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

ELECTRIC DEMAND INSTRUMENT.

Specification of Lettera Patent.

Yatented April 27, IBOG.

Appl cation filed January 16, 1905. Serial No. 241,218.

To allwhom it may concern:

Be it known that .l, WILLIAM J. LLOYD, a citizen of the United States, residing at Pittsfield, in the county of Berkshire and State of Massachusetts, have invented certain new and useful Improvements in Electric Demand Instruments, of which the following is a specfiication.

My present invention relates to an electric measuring instrument adapted to record the limit of a demand or condition in an electric circuit. The particular instrument which I have hereinafter described and illustrated is adapted to record. the maximum flow of current in an electric magnetizing coil during a definite period of time.

The various features of novelty which characterize my invention are pointed out with particularity in the claims annexed to and forming a part of this specification. F or a better understanding of the invention, however, reference may be had to the accompanying drawing, vhioh. is an elevation with parts in section, illustrating an instrw ment embodying my invention, and the descriptive matter relating thereto.

In the drawing, 1 represents a mass of magnetic material which forms a part of the framework of the instrument and the major portion of its magnetic circuit. The magnetic material 1 may or may not be laminated. The member 1 comprises two vertical legs or parts 2 which are inte ally connected at their lower ends by a yo. e portion 3. A- cylindrical member 4 of magnetic material is secured to the yoke parallel to and midway between the legs 2 by ascrew 5. A spool 6 carrying a magnetizing coil 7- surrounds the core 4.

A channeled element in the form of a bent tube 8 preferably formed .of glass is secured in any suitable manner, as by means of set screws 9, in a socket formed for the purpose in the core member 4. Preferably a piece 10 of yielding material is inserted-between the tube and the set-screw. It will be observed that the construction employed for securing the tube 8 in place allows of its vertical ad? justment relative to the core. The tube 8 com rises a main vertical portion which ex-v tBHC s in line with the of the core and a down'wardly-tunied portion 11 whicl'i entends from the unper end of the main por tion. A plrn 12 formed of suitable magsuch as soft iron is placed in the lower end of the tube 8 and is so proportioned as to'move freely in the hollow of the tube. hen the member 12 is in its oxtreme lower position its upper end abia-ts slightly above the upper end of the core A number of solid bodies 13 which may be in the form of bells formedv out of glass,- non-magnetic metal, or the like, are placed in the main portion of the tube above the plunger 12. The bodies 13 are of a diameter slightly less than that of the bore of the tube 8 so as to have free movement therein. The number of balls placed in the tube are sufficient to extend nearly but, not quite to the bend in the tube when the member is in its extreme lower position. After the member 12 and balls 13 are placed in the tube the remainder of the s' ace in the latter is filled with some suitab e dam ing fluid such as glycerin or the like and t. e tube is through the winding 7 a magnetic flux is set up which pasess through circuits each comprising a core member sand member 12, one of the enlargements 14, the corresponding member 2 and a portion of the base 3. One of the fiux paths is indicated by the arrows in the drawing.

It will be observed that each member 2, the corresponding polar enlargement L adjacent half of the yoke or base 3, and core member 4, comprise a nearly closed magnetic circuit. Whenthe member 12 isin its normal position at the bottom of the tube 8 its upper end is about on a level with the lower ges of the polar enlargements 14. Upon the passage of current through the (301i 7 the member 12 is moved upward against the action of gravity to a' position in which the reluctariceiof the path between the upper end of the core 4 and the adjacent polar projectionit; is less than in the original position of the member.

As the current in the winding 7 increases and the flux densities in the core member s and the inner lower tips of the polar enlargemerits 14 are increased, the member 12 is raised higher and higher. By choosing the proper proportion and configuration of arts, the elevation of the member 12 Within imits can be made directly proportional to the current flow in the coil 7. Upon a definite upward movement of the member 12 in re- S ()IS to a predetermined current flow in the coil 7, the ripper ball or body 13 will he moveo to the bend in tee tube 8 and will roll down into the portion 11. (in e further increase of current flow in the coil 7 to o second ore-determined amount, another call or body 13 will be moved iiito the portion 11 of the tube. Similarly, further increases in the emount of current flow occurring from time to time Will cause other bodies 13 to be moved from the chamber fo 'med by th rue-iii portion of the tube 3 into the chamber formed by the portion 11. The halls will only be transferred from the main portion of tube to portion 11 when the oredetee rriiried flow or current is continuedrior an appreciable period or time as the clamping fluid Will prevent the transfer of the balls in response to momentary increases in current fio'wi When the period during which it is desired to obtain a record of the maximum current fifi'vf has'cxpirecl the balls or bodies 13 in the extension 11 may be returned to the meiri portion of the to; e by tilting the letter end eilowizig the balls to run back to their origirial position. By changing the position of the tube relative to the core the instrument may be adjuste'l more or less to obtain a proper rec-or l i Jiiiie in the the :TQQGrZi Obiilifi s of the variations of current flow coil '3 it will be readily understood that this variation may be res; onsive to but? :floe' of in another e ectiic circuit or to potential or other condition of said circeit.

While I have ileioill jfiffi'fe described eiiri llustrated the best form of my invention W known to it will be obvious to those in the art th changes can be mode is the form of the invention disclosed without departing from the spirit thereof.

What I. claim as new and desire to secure by Letters Patent of the United States, is,

i. In combination, a solenoid, a, fixed hollow core therein, a polar extension outside of said solenoid and serving as a path for the magnetic lines of force from end to end of said hollow c e, and a movable core located. within said hollow core and adapted to move outwardly as the magnetomotive force iiicreeses. I r

in com-emotion, a solenoid, a fixed hollow corehaving an extension therefrom the tube cohteioirg viscous magnetic me 1 l tell i troisegnetic tion of said i duce a Whiz tend to e corewio in said hoilovvv core to 120* as the force tic means 5 r indicetiog he lQltZ-lli" merit of the movable c=.

3. in CGZBlJlIliti-iOZl and pole pieces I movable core which the soienoicl es the n agnetom creases.

eombin glorelity of pol piece :ghle core i solenoio as creases, mum H10? 1 w, 1 1 1 to woico t pole meg etoziio to more on rile-ins meet of ti E9. in core portions, e portion or 5: really ioected ii tromegnetic roe transfer 0 115 other A C 9L rl said tube sto obtain a record of the maximu merit of said plunger.

i 11. In combination, e Ler'met through said liquid by said plunger to obtain a permanent record of the maximum change in the position of said plunger.

12. In combination a stationary element having a closed chamber or channel formed in it, a solid indicatin body located in said chamber or channel, and electromagnetic means for permanently changing the location of said body in said element in response to a predetermined change in the condition of an electric circuit.

13. In combination an element having a channel formed in it and filled with viscous liquid, a mass of magnetic material located in said channel, electromagnetic means without said channel for moving said mass of electromagnetic material relative to said channel, and a solid indicating body moved through the channel and permanently changed inlocation in said channel by said mass of magnetic material to record its maximum movement relative to the channel. l 14. In a measuring instrument, a core of l 15. In a measuring instrument, magnetic material arranged to form a closed-magnetic path except for a short gap between one portion of said magnetic material and another portion above the first-mentioned portion, a coil for magnetizing said material, and a movable mass of magnetic material moved upward under the action of the magnetizing coil to a position in which the reluctance of the gap is diminished in a path which does not change he length oi said gap.

In Witness whereof, I have hereunto set my hand this third day of January, 1905.

. WILLIAM J. LLOYD. Witnesses:

ERNEST HARKER, ETHEL M. WEBB. 

